By combining the merits of radiative cooling(RC)and evaporation cooling(EC),radiative coupled evaporative cooling(REC)has attracted considerable attention for sub-ambient cooling purposes.However,for outdoor devices,t...By combining the merits of radiative cooling(RC)and evaporation cooling(EC),radiative coupled evaporative cooling(REC)has attracted considerable attention for sub-ambient cooling purposes.However,for outdoor devices,the interior heating power would increase the working temperature and fire risk,which would suppress their above-ambient heat dissipation capabilities and passive water cycle properties.In this work,we introduced a REC design based on an all-in-one photonic hydrogel for above-ambient heat dissipation and flame retardancy.Unlike conventional design RC film for heat dissipation with limited cooling power and fire risk,REC hydrogel can greatly improve the heat dissipation performance in the daytime with a high workload,indicating a 12.0℃lower temperature than the RC film under the same conditions in the outdoor experiment.In the nighttime with a low workload,RC-assisted adsorption can improve atmospheric water harvesting to ensure EC in the daytime.In addition,our REC hydrogel significantly enhanced flame retardancy by absorbing heat without a corresponding temperature rise,thus mitigating fire risks.Thus,our design shows a promising solution for the thermal management of outdoor devices,delivering outstanding performance in both heat dissipation and flame retardancy.展开更多
Intense evaporation in areas with loess-like sulfate saline soils has resulted in significant ecological challenges that include water shortages and soil salinization.Investigating evaporation rate in loess-like sulfa...Intense evaporation in areas with loess-like sulfate saline soils has resulted in significant ecological challenges that include water shortages and soil salinization.Investigating evaporation rate in loess-like sulfate saline soils under varying salt contents carries crucial implications for understanding regional water loss processes,predicting soil salinization advancement,and formulating effective ecological management strategies.Therefore,this study sampled the loess-like sulfate saline soil that is widely distributed in western China as experimental materials and investigated the impact of different initial salt contents(0.00%,0.50%,1.50%,3.00%,and 5.00%)on the evaporation rate,water content,and temperature of soil.The results showed that the evaporation rate decreased with increasing initial salt content.After a salt accumulation layer formed on the soil surface,the water content of the surface soil fluctuated.An increase in the initial salt content resulted in a corresponding increase in the surface temperature.Considering the evaporation characteristics of loess-like sulfate saline soil and the impact of an anomalous increase in surface soil water content on soil surface resistance,this study proposed a modified evaporation model on the basis of Fujimaki's evaporation model of saline soil by introducing a correction coefficientβto modify the soil surface resistance.A comparison of the calculated evaporation rates before and after the modification with the measured evaporation rates revealed a significant improvement in the calculation accuracy of the modified model,indicating that the modified model is capable of more accurately simulating the evaporation rate of sulfate saline soil with different initial salt contents.This paper proposes an effective method for calculating the evaporation rate of loess-like sulfate saline soils,providing a theoretical basis for evaporation research in saline soil.展开更多
The evaporation ofmicrometer and millimeter liquid drops,involving a liquid-to-vapor phase transition accompanied by mass and energy transfer through the liquid-vapor interface,is encountered in many natural and indus...The evaporation ofmicrometer and millimeter liquid drops,involving a liquid-to-vapor phase transition accompanied by mass and energy transfer through the liquid-vapor interface,is encountered in many natural and industrial processes as well as in numerous engineering applications.Therefore,understanding and predicting the dynamics of evaporating flows have become of primary importance.Recent efforts have been addressed using the method of Smoothed Particle Hydrodynamics(SPH),which has proven to be very efficient in correctly handling the intrinsic complexity introduced by the multiscale nature of the evaporation process.This paper aims to provide an overview of published work on SPH-based simulations related to the evaporation of drops suspended in static and convective environments and impacting on heated solid surfaces.After a brief theoretical account of the main ingredients necessary for the modeling of drop evaporation,the fundamental aspects of SPH are revisited along with the various existing formulations that have been implemented to address the challenges imposed by the physics of evaporating flows.In the following sections,the paper summarizes the results of SPH-based simulations of drop evaporation and ends with a few comments on the limitations of the current state-of-the-art SPHsimulations and future lines of research.展开更多
Porous liquid-conducting micro-heat exchangers have garnered considerable attention for their role in efficient heat dissipation in small electronic devices.This demand highlights the need for advanced mathematical mo...Porous liquid-conducting micro-heat exchangers have garnered considerable attention for their role in efficient heat dissipation in small electronic devices.This demand highlights the need for advanced mathematical models to optimize the selection of mixed heat exchange media and equipment design.A capillary bundle evaporation model for porous liquid-conducting media was developed based on the conjugate mass transfer evaporation rate prediction model of a single capillary tube,supplemented by mercury injection experimental data.Theoretical and experimental comparisons were conducted using 1,2-propanediol-glycerol(PG-VG)mixtures at molar ratios of 1:9,3:7,5:5,and 7:3 at 120,150,and 180℃.The Jouyban-Acree model was implemented to enhance the evaporation rate predictions.For the 7:3 PG-VG mixture at 180℃under the experimental conditions of the thermal medium,the model's error reduced from 16.75%to 10.84%post-correction.Overall,the mean relative error decreased from 11.76%to 5.98%after correction.展开更多
The utilization of solar-driven interfacial evaporation technology is highly important in addressing the energy crisis and water scarcity,primarily because of its affordability and minimal energy usage.Enhancing the p...The utilization of solar-driven interfacial evaporation technology is highly important in addressing the energy crisis and water scarcity,primarily because of its affordability and minimal energy usage.Enhancing the performance of solar energy evaporation and minimizing material degradation during application can be achieved through the design of novel photothermal materials.In solar interfacial evaporation,photothermal materials exhibit a wide range of additional characteristics,but a systematic overview is lacking.This paper encompasses an examination of various categories and principles pertaining to photothermal materials,as well as the structural design considerations for salt-resistant materials.Additionally,we discuss the versatile uses of this appealing technology in different sectors related to energy and the environment.Furthermore,potential solutions to enhance the durability of photothermal materials are also highlighted,such as the rational design of micro/nano-structures,the use of adhesives,the addition of anti-corrosion coatings,and the preparation of self-healing surfaces.The objective of this review is to offer a viable resolution for the logical creation of high-performance photothermal substances,presenting a guide for the forthcoming advancement of solar evaporation technology.展开更多
This review examines the processes of laser heating,melting,evaporation,fragmentation,and breakdown of metal nanoparticles,as well as the dependences and values of the threshold laser parameters that initiate these pr...This review examines the processes of laser heating,melting,evaporation,fragmentation,and breakdown of metal nanoparticles,as well as the dependences and values of the threshold laser parameters that initiate these processes.Literature results are analyzed from experimental studies of these processes with gold,silver,and other nanoparticles,including laser surface melting and evaporation of nanoparticles and Coulomb fragmentation of nanoparticles by ultrashort laser pulses.A theoretical model and description of the thermal mechanisms of mentioned processes with metal(solid)nanoparticles in a liquid(solid)medium,initiated by the action of laser pulses with the threshold fluences,are presented.Comparison of the obtained results with experimental data confirms the accuracy of the model and makes it possible to use them to evaluate the parameters of laser thermal processing of nanoparticles.Applications of the processes include the laser melting,reshaping,and fragmentation of nanoparticles,the formation of nanostructures and nanonetworks,the laser processing of nanoparticles located on substrates,and their cladding on surfaces in various laser nanotechnologies.The use of laser ignition,combustion,and incandescence of nanoparticles is discussed,as is the use of nanoparticle-triggered laser breakdown for spectroscopy.These laser processes are used in photothermal nanotechnologies,nanoenergy,laser processing of nanoparticles,nonlinear optical devices,high-temperature material science,etc.In general,this review presents a modern picture of the state of laser technology and high-temperature processes with nanoparticles and their applications,being focused on the latest publications with an emphasis on recent results from 2021-2024.展开更多
Hydrogel has developed into a very important platform in solar interface evaporator.However,the current hydrogel evaporators are usually three-dimensional evaporators,which will consume a lot of raw materials.Thus,a n...Hydrogel has developed into a very important platform in solar interface evaporator.However,the current hydrogel evaporators are usually three-dimensional evaporators,which will consume a lot of raw materials.Thus,a new two-dimensional hydrogel evaporator is urgently needed to alleviate this problem.Here,a double layer hydrogel evaporator was designed by twice vacuum filtration.Furthermore,through the arched design and the introduction of concentrated brine drainage system,the hydrogel evaporator has enhanced water transportation and tailored water transportation path.Such a unique drainage evaporation system greatly improves the stability of the evaporator.Thereby,a good balance is established between photothermal conversion and water supply,and solar energy is utilized efficiently.It can remain stable in continuous evaporation for up to 12 h with an excellent evaporation rate of 2.70 kg m^(-2)h^(-1)under 1 sun irradiation.Meanwhile,the drainage system realized the 1.8×10^(-10)mol m^(-2)s^(-1)diffusion flux of concentrated brine.Through one-time freeze-drying preparation,an arch-shaped drainage evaporator was used to prepare an evaporation area of more than 20 cm^(2).With the self-made condensate collecting device in outdoor environment,the fresh water yield reaches 7.5 L m^(-2)d^(-1).This provides a new scheme for building a new hydrogel evaporator and solving the fresh water crisis.展开更多
Fiber fabrics have been wildly utilized for solar interracial evaporators to address freshwater scarcity.However,the complex and expensive manufacturing processes remain limited to their scalable development.Herein,a ...Fiber fabrics have been wildly utilized for solar interracial evaporators to address freshwater scarcity.However,the complex and expensive manufacturing processes remain limited to their scalable development.Herein,a fabric-based Janus interracial evaporator is efficiently fabricated on a large scale by integrating an extremely innovative self-designed melt-centrifugal spinning technology with spray coating technology.The prepared fabric-based Janus interfacial evaporator has differential hydrophilicity,uneven surfaces,and channels that allow moisture escape.Benefiting from the excellent photothermai conversion of graphene oxide and the charge transfer actions of titanium dioxide,such a multifunction evaporator can reach a high evaporation rate of 1.72 kg m^(-2)h^(-1)under 1 sun irradiation,a superior antibacterial rate of 99%,excellent photocatalytic degradation,and effective thermoelectric ability simultaneously.Moreover,it also shows fantastic performance in salt resistance,recyclable evaporation,and real desalination,This work demonstrates a high-efficiency,cost-effective,multifunctional,and scalable strategy for high-performance fiber fabrics solar interfacial evaporation.展开更多
Control of the wetting properties of biomimetic functional surfaces is a desired functionality in many applications.In this paper,the photoresist SU-8 was used as fabrication material.A silicon wafer was used as a sub...Control of the wetting properties of biomimetic functional surfaces is a desired functionality in many applications.In this paper,the photoresist SU-8 was used as fabrication material.A silicon wafer was used as a substrate to prepare a biomimetic surface with different surface roughness and micro-pillars arranged in array morphology.The evaporation dynamics and interfacial heat transfer processes of deionised water droplets on the bioinspired microstructure surface were experimentally studied.The study not only proves the feasibility of preparing hydrophilic biomimetic functional surfaces directly through photoresist materials and photolithography technology but also shows that by adjusting the structural parameters and arrangement of the surface micro-pillar structure,the wettability of the biomimetic surface can be significantly linearly regulated,thereby effectively affecting the heat and mass transfer process at the droplet liquid-vapour interface.Analysis of the results shows that by controlling the biomimetic surface microstructure,the wettability can be enhanced by about 22%at most,the uniformity of the temperature distribution at the liquid-vapour interface can be improved by about 34%,and the average evaporation rate can be increased by about 28%.This study aims to provide some guidance for the research on bionic surface design based on photoresist materials.展开更多
A new experimental method is developed to investigate the effect of dissolved substances on the evaporation rate of small water droplets suspended in the atmosphere.The laboratory setup is based on converting a genera...A new experimental method is developed to investigate the effect of dissolved substances on the evaporation rate of small water droplets suspended in the atmosphere.The laboratory setup is based on converting a generated droplet jet of complex structure into a directed flow of evaporating droplets falling in a vertical tube.Images of falling droplets captured by a high-speed camera through a window in the vertical channel wall are used to determine the sizes and velocities of individual droplets.The computational modeling of droplet motion and evaporation proved useful at all stages of the experimental work:from selecting the position of the vertical channel to processing the experimental data.It was found that even a 0.1%mass concentration of the dissolved ionic salt KCl has a considerable effect on decreasing the evaporation rate of the droplets.In contrast,a typical fungicide with a mass concentration of 2.5%has only a slight impact on the evaporation rate.The laboratory results enabled the authors to refine the evaporation model of water droplets to account for the presence of dissolved substances.Modified models of this type are expected to be useful in controling crop spraying and also in other potential applications.展开更多
The evaporation behaviors are crucial for the flame location estimation in liquid rocketengines.This work,for the first time,experimentally reports the sub-millimeter droplet evaporationcharacteristics of the corrosiv...The evaporation behaviors are crucial for the flame location estimation in liquid rocketengines.This work,for the first time,experimentally reports the sub-millimeter droplet evaporationcharacteristics of the corrosive dinitrogen tetroxide(NTO,one prevailing hypergolic oxidizer)athigh ambient pressure up to 4.5 MPa.An in-house corrosion-resistant droplet generator is usedto generate isolated flying droplets of sub-millimeter size,which are then exposed in a gas environ-ment with temperatures between 1010 K and 1210 K and pressures in the range between 2.0 MPaand 4.5 MPa,provided by an optical rapid compression machine.Parallelly,a theoretical modelconsidering both the droplet ambient convection and the NTO dissociation is developed.Resultsindicate that firstly,the present theoretical model that considers the transient droplet-ambient con-vection as well as the temperature and pressure dependent rate of dissociation shows good agree-ment with the experimentally observed droplet lifetime.In addition,the flying droplets velocityregress gradually due to momentum exchange with the ambient,which is more prominent at higherpressure.The evaporation caused droplet size reduction is consistent with the classical D^(2)-law pre-diction,in the present temperature and pressure range.Finally,higher temperature and pressureaccelerate the evaporation and an empirical correlation for the temperature and pressure dependentevaporation rate constant is proposed,which shows good agreement with experiment and simula-tion results.展开更多
Flexible and conformable nanomaterial-based functional hydrogels find promising applications in various fields.However,the controllable manipulation of functional electron/mass transport networks in hydrogels remains ...Flexible and conformable nanomaterial-based functional hydrogels find promising applications in various fields.However,the controllable manipulation of functional electron/mass transport networks in hydrogels remains rather challenging to realize.We describe a general and versatile surfactant-free emulsion construction strategy to customize robust functional hydrogels with programmable hierarchical structures.Significantly,the amphipathy of silk fibroin(SF)and the reinforcement effect of MXene nanosheets produce sable Pickering emulsion without any surfactant.The followed microphase separation and self-cross-linking of the SF chains induced by the solvent exchange convert the composite emulsions into high-performance hydrogels with tunable microstructures and functionalities.As a proof-of-concept,the controllable regulation of the ordered conductive network and the water polarization effect confer the hydrogels with an intriguing electromagnetic interference shielding efficiency(~64 dB).Also,the microstructures of functional hydrogels are modulated to promote mass/heat transfer properties.The amino acids of SF and the surface terminations of MXene help reduce the enthalpy of water evaporation and the hierarchical structures of the hydrogels accelerate evaporation process,expecting far superior evaporation performance(~3.5 kg m^(-2)h^(-1))and salt tolerance capability compared to other hydrogel evaporators.Our findings open a wealth of opportunities for producing functional hydrogel devices with integrated structure-dependent properties.展开更多
Solar interfacial evaporation(SIE),is currently one of the most potential water supply technologies in the remote,insular,and disaster-stricken areas.However,the existence of volatile organic compounds(VOCs)in water d...Solar interfacial evaporation(SIE),is currently one of the most potential water supply technologies in the remote,insular,and disaster-stricken areas.However,the existence of volatile organic compounds(VOCs)in water deteriorates the distillate quality,threatening human health.Herein,we constructed a carbonbased bimetallic(C/FeCo)photothermal membrane by electrospinning technique.Results illustrated that the membrane can catalytically degrade VOCs during SIE with persulfate(PDS)mediation.PDS,as well as phenol,was mainly reacted on the interface of the photothermal membrane instead of in the bulk solution.The interception efficiency of phenol achieved nearly 100%using the C/FeCo membrane during SIE.Hydroxyl radical(•OH),sulfate radical(SO_(4)•−),superoxide radical(O_(2)•−),and singlet oxygen(^(1)O_(2))were identified as the main active substances to degrade VOCs.We also conducted SIE experiments using actual river water to evaluate the practical performance of the C/FeCo membrane.This work holds the promise of VOCs interception during SIE and enlarges the application of solar distillation in water/wastewater treatment.展开更多
In this study,cobalt-incorporated polydopamine coating onto Mn-modified mesoporous silica and successive graphitization treatment make the resulting composite afford abundant porosity,multiple metal active species,pol...In this study,cobalt-incorporated polydopamine coating onto Mn-modified mesoporous silica and successive graphitization treatment make the resulting composite afford abundant porosity,multiple metal active species,polar N sites,and excellent light-to-heat conversion ability.The controlled graphitization temperature was optimized to improve the activity state of metal species.The results reveal that Co_(3)O_(4) nanoparticles incorporated thin-layer carbon formed onto the Mn-confined mesoporous silica,and more Co(Ⅱ)and Mn(Ⅲ)were generated in the MS-Co-500N_(2) compared to MS-Co-500Air,which could cause the accelerated reaction cycles in the potassium peroxymonosulfate complex salt(PMS)activation.The degradation experiments demonstrated that the catalyst almost completely degraded biphenol A within 10 min with the reaction rate constant of 0.56 min−1,nearly 205 times enhancement compared to the MS-Co-500Air.The free radicals trapping and quenching control demonstrated the dominant role of ^(1)O_(2) and·O_(2) in the degradation process.Due to the efficient incorporation of Co_(3)O_(4) nanoparticles and thin-layer carbon,the photothermal conversion properties were explored and utilized for solar-driving interface water evaporation and cleanwater recovery.To explore the practical application possibility in treating complicated polluted wastewater,the MS-Co-500N_(2) materials were fixed on the melamine sponge by Ca ions-trigger alginate crosslinking strategy,and the integrated monolith evaporator shows an excellent water evaporation performance(1.52 kg·m^(−2)·h^(−1))and synchronous pollutant removal in biphenol A(94%,10 min),carbamazepine(92%,10 min),oxytetracycline(84%,20 min)and norfloxacin(84%,20 min).展开更多
Nowadays, one of the most important effects on water resources under climate change is increasing of free water surface evaporation which depends on the increasing of temperature. In basins, where there are no observe...Nowadays, one of the most important effects on water resources under climate change is increasing of free water surface evaporation which depends on the increasing of temperature. In basins, where there are no observed data, free water surface evaporation is taken into account depending on historical temperature and similar data and their long-term statistics. Predicting of real value of evaporation contains some uncertainties. The modeling of evaporation with a small number of predictors has crucial importance on the regions and basins where measurements are not sufficient and/or not exist. In this presented study, daily evaporation prediction models were prepared by using empirical Penman equation, Levenberg-Marquardt algorithm based on 'Feed Forward Back Propagation Artificial Neural Networks (LMANN)', radial basis neural networks (RBNN), generalized regression neural networks (GRNN). When the models were compared, it was noticed that the results of neural network models are statistically more meaningful than the Penman equation.展开更多
Global freshwater scarcity and energy shortages demand integrated solutions.To overcome limitations of traditional solar evaporators,such as salt accumulation,thermal dissipation,and material scalability issues,this s...Global freshwater scarcity and energy shortages demand integrated solutions.To overcome limitations of traditional solar evaporators,such as salt accumulation,thermal dissipation,and material scalability issues,this study presents a biomass-derived three-dimensional(3D)aerogel-based dual-function solar evaporator that simultaneously achieves ultra-high freshwater production and continuous electricity generation.By ingeniously integrating a superhydrophobic inner layer for thermal insulation and buoyancy with a hydrophilic photothermal outer layer for rapid water transport and solar absorption,our design overcomes the trade-offs between evaporation efficiency,salt resistance,and energy loss.The evaporator exhibits exceptional dual performance:an evaporation rate of 3.87 kg m^(-2)h-1(1 sun)and a sustained open-circuit voltage of 222.6 mV,surpassing most reported systems.This synergy originates from ion gradient-driven streaming potentials enabled by selective Na^(+) transport through–COOH/C–OH functionalized microchannels,as verified by molecular dynamics simulations.Crucially,the fabrication process utilizes low-cost biomass materials and scalable techniques,demonstrating significant potential for commercialization.This work not only provides a mechanistic understanding of ion-selective transport in dual-function evaporators but also establishes a paradigm for sustainable co-production of clean water and renewable energy,addressing two pressing global challenges through a single and scalable platform.展开更多
Hygroscopic hydrogel is a promising evaporativecooling material for high-power passive daytime cooling with water self-regeneration.However,undesired solar and environmental heating makes it a challenge to maintain su...Hygroscopic hydrogel is a promising evaporativecooling material for high-power passive daytime cooling with water self-regeneration.However,undesired solar and environmental heating makes it a challenge to maintain sub-ambient daytime cooling.While different strategies have been developed to mitigate heat gains,they inevitably sacrifice the evaporation and water regeneration due to highly coupled thermal and vapor transport.Here,an anisotropic synergistically performed insulation-radiation-evaporation(ASPIRE)cooler is developed by leveraging a dual-alignment structure both internal and external to the hydrogel for coordinated thermal and water transport.The ASPIRE cooler achieves an impressive average sub-ambient cooling temperature of~8.2℃ and a remarkable peak cooling power of 311 W m^(-2)under direct sunlight.Further examining the cooling mechanism reveals that the ASPIRE cooler reduces the solar and environmental heat gains without comprising the evaporation.Moreover,self-sustained multi-day cooling is possible with water self-regeneration at night under both clear and cloudy days.The synergistic design provides new insights toward high-power,sustainable,and all-weather passive cooling applications.展开更多
The evaporation duct which forms above the ocean surface has a significant influence on electromagnetic wave propagation above 2 GHz over the ocean. The effects of horizontal inhomogeneity of evaporation duct on elect...The evaporation duct which forms above the ocean surface has a significant influence on electromagnetic wave propagation above 2 GHz over the ocean. The effects of horizontal inhomogeneity of evaporation duct on electromagnetic wave propagation are investigated, both in numerical simulation and experimental observation methods, in this paper. Firstly, the features of the horizontal inhomogeneity of the evaporation duct are discussed. Then, two typical inhomogeneous cases are simulated and compared with the homogeneous case. The result shows that path loss is significantly higher than that in the homogeneous case when the evaporation duct height （EDH） at the receiver is lower than that at the transmitter. It is also concluded that the horizontal inhomogeneity of the evaporation duct has a significant influence when the EDH is low or when the electromagnetic wave frequency is lower than 13 GHz. Finally, experimental data collected on a 149-km long propagation path in the South China Sea in 2013 are used to verify the conclusion. The experimental results are consis- tent with the simulation results. The horizontal inhomogeneity of evaporation duct should be considered when modeling electromagnetic wave propagation over the ocean.展开更多
Considering the precise composition control on the vacuum refining of high-Mn steel, the behaviors of both Mn evaporation and nitrogen removal from molten Mn steel were investigated via vacuum slag refining in a vacuu...Considering the precise composition control on the vacuum refining of high-Mn steel, the behaviors of both Mn evaporation and nitrogen removal from molten Mn steel were investigated via vacuum slag refining in a vacuum induction furnace. It was found that the reaction interfaces of denitrification and Mn evaporation tend to migrate from the surface of slag layer to the surface of molten steel with the gradual exposure of molten steel during the vacuum slag refining process. Significantly, compared with the experimental group without slag addition, the addition of slag into steel can result in a lower Mn evaporation rate constant of 0.0192 cm·min~(-1) at 370 Pa, while the denitrification rate is almost not affected. Besides, the slag has a stronger inhibitory effect on Mn evaporation than the reduced vacuum pressure. Moreover, the inhibitory effect of the slag layer on Mn evaporation can be weakened with the increase of the initial Mn content in molten steel. The slag layer can work as an inhibitory layer to reduce the Mn evaporation from molten steel, the evaporation reaction of Mn mainly proceeds on the surface of the molten steel. This may be attributed to the Mn mass transfer coefficient for one of reaction at steel/slag interface, mass transfer in molten slag, and evaporation reaction at slag/gas interface is lower than that of evaporation reaction at steel/gas interface. The introduction of slag is proposed for both denitrification and manganese control during the vacuum refining process of Mn steels.展开更多
[Objective] The research aimed to explore the most suitable gravel cover- ing thickness for selenium sand melon in arid region of central Ningxia. [Method] The natural gravel, which was from Nanshantai Region in Zhong...[Objective] The research aimed to explore the most suitable gravel cover- ing thickness for selenium sand melon in arid region of central Ningxia. [Method] The natural gravel, which was from Nanshantai Region in Zhongwei City, Ningxia, was acted as test materials to study the effects of different thicknesses of gravel covering on daily evaporation using evaporator overall weighing method. [Result] The daily evaporation capacity order of the gravel covering thickness was as follows： CK〉HI（5 cm）〉 H2（8 cm）〉 H3（10 cm）〉 H4（15 cm）. Meanwhile, with the increase of test days, the difference of cumulative evaporation capacity between H3 （10 cm） and H4 （15 cm） decreased gradually. Soil evaporation capacity reduced at the pow- er function with the increase of gravel covering thickness, and the decision coeffi- cient of the fitted curve reached to 0.925 5. [Conclusion] With the increase of gravel covering thickness, evaporation capacity of soil reduced gradually, and the soil water content increased gradually. Gravel covering could effectively reduce the evapora- tion. The thicker of covering, the more obvious inhibition effect on evaporation. The thickness of covering should increase moderately to prevent moisture loss from e- vaporation. Gravel inhibition effect on the evaporation wasn＇t obvious when the gravel covering thickness reached more than 10 cm. 10 cm gravel covering was the most appropriate thickness for local natural condition. The soil evaporation capacity along with the change of gravel covering could be simulated with power function e- quation Y=at^b.展开更多
基金financially supported by the Science and Technology Innovation Program of Hunan Province(2024RC3003)the Central South University Innovation-Driven Research Programme(2023CXQD012)the Initiative for Sustainable Energy for its financial support。
文摘By combining the merits of radiative cooling(RC)and evaporation cooling(EC),radiative coupled evaporative cooling(REC)has attracted considerable attention for sub-ambient cooling purposes.However,for outdoor devices,the interior heating power would increase the working temperature and fire risk,which would suppress their above-ambient heat dissipation capabilities and passive water cycle properties.In this work,we introduced a REC design based on an all-in-one photonic hydrogel for above-ambient heat dissipation and flame retardancy.Unlike conventional design RC film for heat dissipation with limited cooling power and fire risk,REC hydrogel can greatly improve the heat dissipation performance in the daytime with a high workload,indicating a 12.0℃lower temperature than the RC film under the same conditions in the outdoor experiment.In the nighttime with a low workload,RC-assisted adsorption can improve atmospheric water harvesting to ensure EC in the daytime.In addition,our REC hydrogel significantly enhanced flame retardancy by absorbing heat without a corresponding temperature rise,thus mitigating fire risks.Thus,our design shows a promising solution for the thermal management of outdoor devices,delivering outstanding performance in both heat dissipation and flame retardancy.
基金supported by the National Natural Science Foundation of China(51769013,52168052)。
文摘Intense evaporation in areas with loess-like sulfate saline soils has resulted in significant ecological challenges that include water shortages and soil salinization.Investigating evaporation rate in loess-like sulfate saline soils under varying salt contents carries crucial implications for understanding regional water loss processes,predicting soil salinization advancement,and formulating effective ecological management strategies.Therefore,this study sampled the loess-like sulfate saline soil that is widely distributed in western China as experimental materials and investigated the impact of different initial salt contents(0.00%,0.50%,1.50%,3.00%,and 5.00%)on the evaporation rate,water content,and temperature of soil.The results showed that the evaporation rate decreased with increasing initial salt content.After a salt accumulation layer formed on the soil surface,the water content of the surface soil fluctuated.An increase in the initial salt content resulted in a corresponding increase in the surface temperature.Considering the evaporation characteristics of loess-like sulfate saline soil and the impact of an anomalous increase in surface soil water content on soil surface resistance,this study proposed a modified evaporation model on the basis of Fujimaki's evaporation model of saline soil by introducing a correction coefficientβto modify the soil surface resistance.A comparison of the calculated evaporation rates before and after the modification with the measured evaporation rates revealed a significant improvement in the calculation accuracy of the modified model,indicating that the modified model is capable of more accurately simulating the evaporation rate of sulfate saline soil with different initial salt contents.This paper proposes an effective method for calculating the evaporation rate of loess-like sulfate saline soils,providing a theoretical basis for evaporation research in saline soil.
文摘The evaporation ofmicrometer and millimeter liquid drops,involving a liquid-to-vapor phase transition accompanied by mass and energy transfer through the liquid-vapor interface,is encountered in many natural and industrial processes as well as in numerous engineering applications.Therefore,understanding and predicting the dynamics of evaporating flows have become of primary importance.Recent efforts have been addressed using the method of Smoothed Particle Hydrodynamics(SPH),which has proven to be very efficient in correctly handling the intrinsic complexity introduced by the multiscale nature of the evaporation process.This paper aims to provide an overview of published work on SPH-based simulations related to the evaporation of drops suspended in static and convective environments and impacting on heated solid surfaces.After a brief theoretical account of the main ingredients necessary for the modeling of drop evaporation,the fundamental aspects of SPH are revisited along with the various existing formulations that have been implemented to address the challenges imposed by the physics of evaporating flows.In the following sections,the paper summarizes the results of SPH-based simulations of drop evaporation and ends with a few comments on the limitations of the current state-of-the-art SPHsimulations and future lines of research.
基金the funding support of National Natural Science Foundation of China(21978204)。
文摘Porous liquid-conducting micro-heat exchangers have garnered considerable attention for their role in efficient heat dissipation in small electronic devices.This demand highlights the need for advanced mathematical models to optimize the selection of mixed heat exchange media and equipment design.A capillary bundle evaporation model for porous liquid-conducting media was developed based on the conjugate mass transfer evaporation rate prediction model of a single capillary tube,supplemented by mercury injection experimental data.Theoretical and experimental comparisons were conducted using 1,2-propanediol-glycerol(PG-VG)mixtures at molar ratios of 1:9,3:7,5:5,and 7:3 at 120,150,and 180℃.The Jouyban-Acree model was implemented to enhance the evaporation rate predictions.For the 7:3 PG-VG mixture at 180℃under the experimental conditions of the thermal medium,the model's error reduced from 16.75%to 10.84%post-correction.Overall,the mean relative error decreased from 11.76%to 5.98%after correction.
基金supported by Zhejiang Provincial Natural Science Foundation of China(No.LR23C160001)Scientific Research Startup Foundation of Zhejiang Ocean University(No.11034150220006).
文摘The utilization of solar-driven interfacial evaporation technology is highly important in addressing the energy crisis and water scarcity,primarily because of its affordability and minimal energy usage.Enhancing the performance of solar energy evaporation and minimizing material degradation during application can be achieved through the design of novel photothermal materials.In solar interfacial evaporation,photothermal materials exhibit a wide range of additional characteristics,but a systematic overview is lacking.This paper encompasses an examination of various categories and principles pertaining to photothermal materials,as well as the structural design considerations for salt-resistant materials.Additionally,we discuss the versatile uses of this appealing technology in different sectors related to energy and the environment.Furthermore,potential solutions to enhance the durability of photothermal materials are also highlighted,such as the rational design of micro/nano-structures,the use of adhesives,the addition of anti-corrosion coatings,and the preparation of self-healing surfaces.The objective of this review is to offer a viable resolution for the logical creation of high-performance photothermal substances,presenting a guide for the forthcoming advancement of solar evaporation technology.
文摘This review examines the processes of laser heating,melting,evaporation,fragmentation,and breakdown of metal nanoparticles,as well as the dependences and values of the threshold laser parameters that initiate these processes.Literature results are analyzed from experimental studies of these processes with gold,silver,and other nanoparticles,including laser surface melting and evaporation of nanoparticles and Coulomb fragmentation of nanoparticles by ultrashort laser pulses.A theoretical model and description of the thermal mechanisms of mentioned processes with metal(solid)nanoparticles in a liquid(solid)medium,initiated by the action of laser pulses with the threshold fluences,are presented.Comparison of the obtained results with experimental data confirms the accuracy of the model and makes it possible to use them to evaluate the parameters of laser thermal processing of nanoparticles.Applications of the processes include the laser melting,reshaping,and fragmentation of nanoparticles,the formation of nanostructures and nanonetworks,the laser processing of nanoparticles located on substrates,and their cladding on surfaces in various laser nanotechnologies.The use of laser ignition,combustion,and incandescence of nanoparticles is discussed,as is the use of nanoparticle-triggered laser breakdown for spectroscopy.These laser processes are used in photothermal nanotechnologies,nanoenergy,laser processing of nanoparticles,nonlinear optical devices,high-temperature material science,etc.In general,this review presents a modern picture of the state of laser technology and high-temperature processes with nanoparticles and their applications,being focused on the latest publications with an emphasis on recent results from 2021-2024.
基金the financial support of the National Natural Science Foundation of China(No.52075309)the Youth Innovation Team of Shaanxi Universities(21JP021)。
文摘Hydrogel has developed into a very important platform in solar interface evaporator.However,the current hydrogel evaporators are usually three-dimensional evaporators,which will consume a lot of raw materials.Thus,a new two-dimensional hydrogel evaporator is urgently needed to alleviate this problem.Here,a double layer hydrogel evaporator was designed by twice vacuum filtration.Furthermore,through the arched design and the introduction of concentrated brine drainage system,the hydrogel evaporator has enhanced water transportation and tailored water transportation path.Such a unique drainage evaporation system greatly improves the stability of the evaporator.Thereby,a good balance is established between photothermal conversion and water supply,and solar energy is utilized efficiently.It can remain stable in continuous evaporation for up to 12 h with an excellent evaporation rate of 2.70 kg m^(-2)h^(-1)under 1 sun irradiation.Meanwhile,the drainage system realized the 1.8×10^(-10)mol m^(-2)s^(-1)diffusion flux of concentrated brine.Through one-time freeze-drying preparation,an arch-shaped drainage evaporator was used to prepare an evaporation area of more than 20 cm^(2).With the self-made condensate collecting device in outdoor environment,the fresh water yield reaches 7.5 L m^(-2)d^(-1).This provides a new scheme for building a new hydrogel evaporator and solving the fresh water crisis.
基金the National Key Research and Development Program of China(Grant No.2022YFC3901902)the National Natural Science Foundation of China(Grant Nos.52203037,52103031,and 52073107)。
文摘Fiber fabrics have been wildly utilized for solar interracial evaporators to address freshwater scarcity.However,the complex and expensive manufacturing processes remain limited to their scalable development.Herein,a fabric-based Janus interracial evaporator is efficiently fabricated on a large scale by integrating an extremely innovative self-designed melt-centrifugal spinning technology with spray coating technology.The prepared fabric-based Janus interfacial evaporator has differential hydrophilicity,uneven surfaces,and channels that allow moisture escape.Benefiting from the excellent photothermai conversion of graphene oxide and the charge transfer actions of titanium dioxide,such a multifunction evaporator can reach a high evaporation rate of 1.72 kg m^(-2)h^(-1)under 1 sun irradiation,a superior antibacterial rate of 99%,excellent photocatalytic degradation,and effective thermoelectric ability simultaneously.Moreover,it also shows fantastic performance in salt resistance,recyclable evaporation,and real desalination,This work demonstrates a high-efficiency,cost-effective,multifunctional,and scalable strategy for high-performance fiber fabrics solar interfacial evaporation.
基金supported by H2020-MSCA-RISE-778104–ThermaSMART,Royal Society(IEC\NSFC\211210)doctoral degree scholarship of China Scholarship Council(CSC).
文摘Control of the wetting properties of biomimetic functional surfaces is a desired functionality in many applications.In this paper,the photoresist SU-8 was used as fabrication material.A silicon wafer was used as a substrate to prepare a biomimetic surface with different surface roughness and micro-pillars arranged in array morphology.The evaporation dynamics and interfacial heat transfer processes of deionised water droplets on the bioinspired microstructure surface were experimentally studied.The study not only proves the feasibility of preparing hydrophilic biomimetic functional surfaces directly through photoresist materials and photolithography technology but also shows that by adjusting the structural parameters and arrangement of the surface micro-pillar structure,the wettability of the biomimetic surface can be significantly linearly regulated,thereby effectively affecting the heat and mass transfer process at the droplet liquid-vapour interface.Analysis of the results shows that by controlling the biomimetic surface microstructure,the wettability can be enhanced by about 22%at most,the uniformity of the temperature distribution at the liquid-vapour interface can be improved by about 34%,and the average evaporation rate can be increased by about 28%.This study aims to provide some guidance for the research on bionic surface design based on photoresist materials.
基金financially supported by the Russian Science Foundation(project No.24-29-00303:https://rscf.ru/project/24-29-00303/,accessed on 01 July 2025).
文摘A new experimental method is developed to investigate the effect of dissolved substances on the evaporation rate of small water droplets suspended in the atmosphere.The laboratory setup is based on converting a generated droplet jet of complex structure into a directed flow of evaporating droplets falling in a vertical tube.Images of falling droplets captured by a high-speed camera through a window in the vertical channel wall are used to determine the sizes and velocities of individual droplets.The computational modeling of droplet motion and evaporation proved useful at all stages of the experimental work:from selecting the position of the vertical channel to processing the experimental data.It was found that even a 0.1%mass concentration of the dissolved ionic salt KCl has a considerable effect on decreasing the evaporation rate of the droplets.In contrast,a typical fungicide with a mass concentration of 2.5%has only a slight impact on the evaporation rate.The laboratory results enabled the authors to refine the evaporation model of water droplets to account for the presence of dissolved substances.Modified models of this type are expected to be useful in controling crop spraying and also in other potential applications.
基金supported by the Natural Science Foundation of China(No.52236001)The support from Research Grants Council of Hong Kong,China(No.CityU 15218820)was also appreciated。
文摘The evaporation behaviors are crucial for the flame location estimation in liquid rocketengines.This work,for the first time,experimentally reports the sub-millimeter droplet evaporationcharacteristics of the corrosive dinitrogen tetroxide(NTO,one prevailing hypergolic oxidizer)athigh ambient pressure up to 4.5 MPa.An in-house corrosion-resistant droplet generator is usedto generate isolated flying droplets of sub-millimeter size,which are then exposed in a gas environ-ment with temperatures between 1010 K and 1210 K and pressures in the range between 2.0 MPaand 4.5 MPa,provided by an optical rapid compression machine.Parallelly,a theoretical modelconsidering both the droplet ambient convection and the NTO dissociation is developed.Resultsindicate that firstly,the present theoretical model that considers the transient droplet-ambient con-vection as well as the temperature and pressure dependent rate of dissociation shows good agree-ment with the experimentally observed droplet lifetime.In addition,the flying droplets velocityregress gradually due to momentum exchange with the ambient,which is more prominent at higherpressure.The evaporation caused droplet size reduction is consistent with the classical D^(2)-law pre-diction,in the present temperature and pressure range.Finally,higher temperature and pressureaccelerate the evaporation and an empirical correlation for the temperature and pressure dependentevaporation rate constant is proposed,which shows good agreement with experiment and simula-tion results.
基金support from the National Natural Science Foundation of China(Nos.51922020,52273064 and 52221006)the Fundamental Research Funds for the Central Universities(BHYC1707B)is gratefully acknowledged.
文摘Flexible and conformable nanomaterial-based functional hydrogels find promising applications in various fields.However,the controllable manipulation of functional electron/mass transport networks in hydrogels remains rather challenging to realize.We describe a general and versatile surfactant-free emulsion construction strategy to customize robust functional hydrogels with programmable hierarchical structures.Significantly,the amphipathy of silk fibroin(SF)and the reinforcement effect of MXene nanosheets produce sable Pickering emulsion without any surfactant.The followed microphase separation and self-cross-linking of the SF chains induced by the solvent exchange convert the composite emulsions into high-performance hydrogels with tunable microstructures and functionalities.As a proof-of-concept,the controllable regulation of the ordered conductive network and the water polarization effect confer the hydrogels with an intriguing electromagnetic interference shielding efficiency(~64 dB).Also,the microstructures of functional hydrogels are modulated to promote mass/heat transfer properties.The amino acids of SF and the surface terminations of MXene help reduce the enthalpy of water evaporation and the hierarchical structures of the hydrogels accelerate evaporation process,expecting far superior evaporation performance(~3.5 kg m^(-2)h^(-1))and salt tolerance capability compared to other hydrogel evaporators.Our findings open a wealth of opportunities for producing functional hydrogel devices with integrated structure-dependent properties.
基金the National Natural Science Foundation of China(No.52070052)the National Natural Science Foundation of China(No.52300082)+3 种基金National Key Research and Development Program of China(No.2022YFB3805903)the State Key Laboratory of Urban Water Resource and Environment in HIT of China(No.2022TS14)the China Postdoctoral Science Foundation(No.2023M730881)Postdoctoral Fellowship Program of CPSF(No.GZB20230964)。
文摘Solar interfacial evaporation(SIE),is currently one of the most potential water supply technologies in the remote,insular,and disaster-stricken areas.However,the existence of volatile organic compounds(VOCs)in water deteriorates the distillate quality,threatening human health.Herein,we constructed a carbonbased bimetallic(C/FeCo)photothermal membrane by electrospinning technique.Results illustrated that the membrane can catalytically degrade VOCs during SIE with persulfate(PDS)mediation.PDS,as well as phenol,was mainly reacted on the interface of the photothermal membrane instead of in the bulk solution.The interception efficiency of phenol achieved nearly 100%using the C/FeCo membrane during SIE.Hydroxyl radical(•OH),sulfate radical(SO_(4)•−),superoxide radical(O_(2)•−),and singlet oxygen(^(1)O_(2))were identified as the main active substances to degrade VOCs.We also conducted SIE experiments using actual river water to evaluate the practical performance of the C/FeCo membrane.This work holds the promise of VOCs interception during SIE and enlarges the application of solar distillation in water/wastewater treatment.
基金supported by the National Natural Science Foundation of China(No.21908085)the China Postdoctoral Science Foundation(No.2023M731422)+3 种基金and the Science and Technology Plan School-Enterprise Cooperation Industry-University-Research Forward-Looking Project of Zhangjiagang(No.ZKYY2341)Suzhou Hospital Association Infection Management Special Research(No.SZSYYXH-2023-ZY1)Suzhou Medical Key Discipline of Occupational Medicine(No.SZXK202115)Jiangsu Undergraduate Innovative Training Program(No.SJCX23_2163).
文摘In this study,cobalt-incorporated polydopamine coating onto Mn-modified mesoporous silica and successive graphitization treatment make the resulting composite afford abundant porosity,multiple metal active species,polar N sites,and excellent light-to-heat conversion ability.The controlled graphitization temperature was optimized to improve the activity state of metal species.The results reveal that Co_(3)O_(4) nanoparticles incorporated thin-layer carbon formed onto the Mn-confined mesoporous silica,and more Co(Ⅱ)and Mn(Ⅲ)were generated in the MS-Co-500N_(2) compared to MS-Co-500Air,which could cause the accelerated reaction cycles in the potassium peroxymonosulfate complex salt(PMS)activation.The degradation experiments demonstrated that the catalyst almost completely degraded biphenol A within 10 min with the reaction rate constant of 0.56 min−1,nearly 205 times enhancement compared to the MS-Co-500Air.The free radicals trapping and quenching control demonstrated the dominant role of ^(1)O_(2) and·O_(2) in the degradation process.Due to the efficient incorporation of Co_(3)O_(4) nanoparticles and thin-layer carbon,the photothermal conversion properties were explored and utilized for solar-driving interface water evaporation and cleanwater recovery.To explore the practical application possibility in treating complicated polluted wastewater,the MS-Co-500N_(2) materials were fixed on the melamine sponge by Ca ions-trigger alginate crosslinking strategy,and the integrated monolith evaporator shows an excellent water evaporation performance(1.52 kg·m^(−2)·h^(−1))and synchronous pollutant removal in biphenol A(94%,10 min),carbamazepine(92%,10 min),oxytetracycline(84%,20 min)and norfloxacin(84%,20 min).
文摘Nowadays, one of the most important effects on water resources under climate change is increasing of free water surface evaporation which depends on the increasing of temperature. In basins, where there are no observed data, free water surface evaporation is taken into account depending on historical temperature and similar data and their long-term statistics. Predicting of real value of evaporation contains some uncertainties. The modeling of evaporation with a small number of predictors has crucial importance on the regions and basins where measurements are not sufficient and/or not exist. In this presented study, daily evaporation prediction models were prepared by using empirical Penman equation, Levenberg-Marquardt algorithm based on 'Feed Forward Back Propagation Artificial Neural Networks (LMANN)', radial basis neural networks (RBNN), generalized regression neural networks (GRNN). When the models were compared, it was noticed that the results of neural network models are statistically more meaningful than the Penman equation.
文摘Global freshwater scarcity and energy shortages demand integrated solutions.To overcome limitations of traditional solar evaporators,such as salt accumulation,thermal dissipation,and material scalability issues,this study presents a biomass-derived three-dimensional(3D)aerogel-based dual-function solar evaporator that simultaneously achieves ultra-high freshwater production and continuous electricity generation.By ingeniously integrating a superhydrophobic inner layer for thermal insulation and buoyancy with a hydrophilic photothermal outer layer for rapid water transport and solar absorption,our design overcomes the trade-offs between evaporation efficiency,salt resistance,and energy loss.The evaporator exhibits exceptional dual performance:an evaporation rate of 3.87 kg m^(-2)h-1(1 sun)and a sustained open-circuit voltage of 222.6 mV,surpassing most reported systems.This synergy originates from ion gradient-driven streaming potentials enabled by selective Na^(+) transport through–COOH/C–OH functionalized microchannels,as verified by molecular dynamics simulations.Crucially,the fabrication process utilizes low-cost biomass materials and scalable techniques,demonstrating significant potential for commercialization.This work not only provides a mechanistic understanding of ion-selective transport in dual-function evaporators but also establishes a paradigm for sustainable co-production of clean water and renewable energy,addressing two pressing global challenges through a single and scalable platform.
基金financially supported by the Young Scientists Fund of National Natural Science Foundation of China(Grant No.52303106)Research Grants Council of Hong Kong SAR(16200720)+3 种基金Environment and Conservation Fund of Hong Kong SAR(Project No.21/2022)Research Institute of Sports Science and Technology(Project No.P0043535)Research Institute of Advanced Manufacturing(Project No.P0046125)the start-up fund for new recruits of Poly U(Project No.P0038855 and P0038858)。
文摘Hygroscopic hydrogel is a promising evaporativecooling material for high-power passive daytime cooling with water self-regeneration.However,undesired solar and environmental heating makes it a challenge to maintain sub-ambient daytime cooling.While different strategies have been developed to mitigate heat gains,they inevitably sacrifice the evaporation and water regeneration due to highly coupled thermal and vapor transport.Here,an anisotropic synergistically performed insulation-radiation-evaporation(ASPIRE)cooler is developed by leveraging a dual-alignment structure both internal and external to the hydrogel for coordinated thermal and water transport.The ASPIRE cooler achieves an impressive average sub-ambient cooling temperature of~8.2℃ and a remarkable peak cooling power of 311 W m^(-2)under direct sunlight.Further examining the cooling mechanism reveals that the ASPIRE cooler reduces the solar and environmental heat gains without comprising the evaporation.Moreover,self-sustained multi-day cooling is possible with water self-regeneration at night under both clear and cloudy days.The synergistic design provides new insights toward high-power,sustainable,and all-weather passive cooling applications.
基金Project supported by the National Natural Science Foundation of China(Grant No.11174235)the Fundamental Research Funds for the Central Universities(Grant No.3102014JC02010301)
文摘The evaporation duct which forms above the ocean surface has a significant influence on electromagnetic wave propagation above 2 GHz over the ocean. The effects of horizontal inhomogeneity of evaporation duct on electromagnetic wave propagation are investigated, both in numerical simulation and experimental observation methods, in this paper. Firstly, the features of the horizontal inhomogeneity of the evaporation duct are discussed. Then, two typical inhomogeneous cases are simulated and compared with the homogeneous case. The result shows that path loss is significantly higher than that in the homogeneous case when the evaporation duct height （EDH） at the receiver is lower than that at the transmitter. It is also concluded that the horizontal inhomogeneity of the evaporation duct has a significant influence when the EDH is low or when the electromagnetic wave frequency is lower than 13 GHz. Finally, experimental data collected on a 149-km long propagation path in the South China Sea in 2013 are used to verify the conclusion. The experimental results are consis- tent with the simulation results. The horizontal inhomogeneity of evaporation duct should be considered when modeling electromagnetic wave propagation over the ocean.
基金financially supported by the National Natural Science Foundation of China (No.51874021)。
文摘Considering the precise composition control on the vacuum refining of high-Mn steel, the behaviors of both Mn evaporation and nitrogen removal from molten Mn steel were investigated via vacuum slag refining in a vacuum induction furnace. It was found that the reaction interfaces of denitrification and Mn evaporation tend to migrate from the surface of slag layer to the surface of molten steel with the gradual exposure of molten steel during the vacuum slag refining process. Significantly, compared with the experimental group without slag addition, the addition of slag into steel can result in a lower Mn evaporation rate constant of 0.0192 cm·min~(-1) at 370 Pa, while the denitrification rate is almost not affected. Besides, the slag has a stronger inhibitory effect on Mn evaporation than the reduced vacuum pressure. Moreover, the inhibitory effect of the slag layer on Mn evaporation can be weakened with the increase of the initial Mn content in molten steel. The slag layer can work as an inhibitory layer to reduce the Mn evaporation from molten steel, the evaporation reaction of Mn mainly proceeds on the surface of the molten steel. This may be attributed to the Mn mass transfer coefficient for one of reaction at steel/slag interface, mass transfer in molten slag, and evaporation reaction at slag/gas interface is lower than that of evaporation reaction at steel/gas interface. The introduction of slag is proposed for both denitrification and manganese control during the vacuum refining process of Mn steels.
基金Supported by Natural Science Research Foundation Item of Ningxia University,China(ZR1208)Science and Technology Research Item of Ningxia Colleges and Universities,China(NGY2014065)~~
文摘[Objective] The research aimed to explore the most suitable gravel cover- ing thickness for selenium sand melon in arid region of central Ningxia. [Method] The natural gravel, which was from Nanshantai Region in Zhongwei City, Ningxia, was acted as test materials to study the effects of different thicknesses of gravel covering on daily evaporation using evaporator overall weighing method. [Result] The daily evaporation capacity order of the gravel covering thickness was as follows： CK〉HI（5 cm）〉 H2（8 cm）〉 H3（10 cm）〉 H4（15 cm）. Meanwhile, with the increase of test days, the difference of cumulative evaporation capacity between H3 （10 cm） and H4 （15 cm） decreased gradually. Soil evaporation capacity reduced at the pow- er function with the increase of gravel covering thickness, and the decision coeffi- cient of the fitted curve reached to 0.925 5. [Conclusion] With the increase of gravel covering thickness, evaporation capacity of soil reduced gradually, and the soil water content increased gradually. Gravel covering could effectively reduce the evapora- tion. The thicker of covering, the more obvious inhibition effect on evaporation. The thickness of covering should increase moderately to prevent moisture loss from e- vaporation. Gravel inhibition effect on the evaporation wasn＇t obvious when the gravel covering thickness reached more than 10 cm. 10 cm gravel covering was the most appropriate thickness for local natural condition. The soil evaporation capacity along with the change of gravel covering could be simulated with power function e- quation Y=at^b.
